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Receive webhook request

Express middleware receives incoming HTTP request to webhook endpoint and extracts path, method, headers, and body.

Lookup webhook registration

Query database to find workflow associated with webhook path and validate it exists and is active.

Load workflow definition

Retrieve complete workflow definition including all nodes, connections, credentials, and settings from database.

Create execution record

Insert new execution entry in database with pending status, workflow ID, trigger data, and timestamp.

Initialize WorkflowExecute

Create WorkflowExecute instance with workflow definition, execution mode, and initial trigger data.

Execute workflow nodes

Traverse workflow graph executing nodes in order, passing data between nodes, handling branching, and managing node credentials.

Store binary data

Save binary files to filesystem or S3 bucket and store reference in execution data.

Update execution status

Update execution record in database with success/error status, output data, duration, and error details if failed.

Publish execution events

Emit execution completion events to event bus for audit logging, webhooks, and UI updates.

Send webhook response

Return HTTP response to original webhook caller with execution results or acknowledgment.